Heap / Priority Queue

Problems using heap data structure

32 lessons
82 min

Lessons

1. What is Heap / Priority Queue

Pattern overview

2m

2. Prerequisites

What you need first

1m

3. When to Use

Pattern triggers

2m

4. When NOT to Use

Avoid forcing this pattern

2m

5. LeetCode 703 Kth Largest Element in a Stream - Problem Statement

The problem

2m1 problems

6. LeetCode 703 Kth Largest Element in a Stream - Solution

The core idea

3m

7. LeetCode 703 Kth Largest Element in a Stream - Example and Complexity Analysis

Walkthrough and analysis

3m

8. LeetCode 703 Kth Largest Element in a Stream - Implementation

The approach

4m1 problems

9. LeetCode 215 Kth Largest Element in an Array - Problem Statement

The problem

2m1 problems

10. Quiz: Heap for Kth Largest

Test your understanding

2m1 problems

11. LeetCode 215 Kth Largest Element in an Array - Why Naive Fails

The trap

2m

12. LeetCode 215 Kth Largest Element in an Array - Solution

The core idea

3m

13. LeetCode 215 Kth Largest Element in an Array - Example and Complexity Analysis

Walkthrough and analysis

3m

14. LeetCode 215 Kth Largest Element in an Array - Implementation

The approach

4m1 problems

15. LeetCode 973 K Closest Points to Origin - Problem Statement

The problem

2m1 problems

16. LeetCode 973 K Closest Points to Origin - Why Naive Fails

The trap

2m

17. LeetCode 973 K Closest Points to Origin - Solution

The core idea

3m

18. LeetCode 973 K Closest Points to Origin - Example and Complexity Analysis

Walkthrough and analysis

3m

19. LeetCode 973 K Closest Points to Origin - Implementation

The approach

4m1 problems

20. LeetCode 621 Task Scheduler - Problem Statement

The problem

2m1 problems

21. LeetCode 621 Task Scheduler - Why Naive Fails

The trap

2m

22. LeetCode 621 Task Scheduler - Solution

The core idea

3m

23. LeetCode 621 Task Scheduler - Example and Complexity Analysis

Walkthrough and analysis

3m

24. LeetCode 621 Task Scheduler - Implementation

The approach

4m1 problems

25. LeetCode 295 Find Median from Data Stream - Problem Statement

The problem

2m1 problems

26. Quiz: Streaming Median

Test your understanding

2m1 problems

27. LeetCode 295 Find Median from Data Stream - Why Naive Fails

The trap

2m

28. LeetCode 295 Find Median from Data Stream - Solution

The core idea

3m

29. LeetCode 295 Find Median from Data Stream - Example and Complexity Analysis

Walkthrough and analysis

3m

30. LeetCode 295 Find Median from Data Stream - Implementation

The approach

4m1 problems

31. Common Mistakes

Common errors to avoid

2m

32. Section Recap

Summary

1m

Practice Problems

1.
LeetCode 104 - Maximum Depth of Binary Treeleetcodeeasy
2.
LeetCode 100 - Same Treeleetcodemedium
3.
LeetCode 572 - Subtree of Another Treeleetcodemedium
4.
LeetCode 235 - Lowest Common Ancestor of a Binary Search Treeleetcodehard
5.
LeetCode 102 - Binary Tree Level Order Traversalleetcodemedium
6.
LeetCode 230 - Kth Smallest Element in a BSTleetcodemedium
7.
LeetCode 105 - Construct Binary Tree from Preorder and Inorder Traversalleetcodehard
8.
LeetCode 1801 - Number of Orders in the Backlogleetcodemedium
9.
LeetCode 1834 - Single-Threaded CPUleetcodemedium
10.
LeetCode 1882 - Process Tasks Using Serversleetcodemedium
11.
LeetCode 1942 - The Number of the Smallest Unoccupied Chairleetcodemedium
12.
LeetCode 2182 - Construct String With Repeat Limitleetcodemedium
13.
LeetCode 2233 - Maximum Product After K Incrementsleetcodemedium
14.
LeetCode 2402 - Meeting Rooms IIIleetcodehard
15.
LeetCode 2462 - Total Cost to Hire K Workersleetcodemedium
16.
LeetCode 2542 - Maximum Subsequence Scoreleetcodemedium
17.
LeetCode 3066 - Minimum Operations to Exceed Threshold Value IIleetcodemedium
18.
LeetCode 3362 - Zero Array Transformation IIIleetcodemedium
19.
LeetCode 3462 - Maximum Sum With at Most K Elementsleetcodemedium
20.
LeetCode 1026 - Maximum Difference Between Node and Ancestorleetcodemedium
21.
LeetCode 1110 - Delete Nodes And Return Forestleetcodemedium
22.
LeetCode 1339 - Maximum Product of Splitted Binary Treeleetcodemedium
23.
LeetCode 1372 - Longest ZigZag Path in a Binary Treeleetcodemedium
24.
LeetCode 1448 - Count Good Nodes in Binary Treeleetcodemedium
25.
LeetCode 1457 - Pseudo-Palindromic Paths in a Binary Treeleetcodemedium
26.
LeetCode 1609 - Even Odd Treeleetcodemedium
27.
LeetCode 2096 - Step-By-Step Directions From a Binary Tree Node to Anotherleetcodemedium
28.
LeetCode 2385 - Amount of Time for Binary Tree to Be Infectedleetcodemedium
29.
LeetCode 2415 - Reverse Odd Levels of Binary Treeleetcodemedium
30.
LeetCode 2471 - Minimum Number of Operations to Sort a Binary Tree by Levelleetcodemedium
31.
LeetCode 2641 - Cousins in Binary Tree IIleetcodemedium
32.
LeetCode 3203 - Find Minimum Diameter After Merging Two Treesleetcodehard

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